title: Protective effect of baicalin against multiple ultraviolet B exposure-mediated injuries in C57BL/6 mouse skin.
abstract: Multiple exposures to solar ultraviolet (UV) radiation cause critical damage to skin that may lead to the development of several cutaneous disorders including skin cancer. Protection against sun-induced damage is therefore a highly desirable goal. Chemoprevention via plant-based agents may be a useful approach for the prevention? of UV-induced neoplasia. In this study, we assessed (1) whether baicalin protected against multiple UVB exposure-mediated damage in skin of C57BL/6 mice and (2) the underlying mechanisms. C57BL/6 mice were topically pretreated with baicalin (1 mg/cm(2) skin area/mouse/100 μL acetone) and were exposed to UVB 30 min later (180 mJ/cm(2), on alternate days × 10 exposures). The animals were sacrificed 24 h after the last UVB exposure. Skin edema, histopathology changes, Ki-67, PCNA, and COX-2 were assessed to determine UVB induced damage. Multiple exposures of C57BL/6 mice to UVB resulted in an increase in skin edema and hyperplasia. Topical application of baicalin prior to UVB radiation resulted in a significant inhibition of Ki-67, PCNA and COX-2 expression. These protective effects of baicalin may also inhibit UVB-induced skin carcinogenesis. Based on this data, we suggest that baicalin could be developed as an agent for the management of conditions elicited by multiple UV exposures, including skin cancer.
authors.affiliation: Department of Dermatology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Bing-rong
authors.initials: BR
authors.lastname: Zhou
authors.forename: Wen-li
authors.initials: WL
authors.lastname: Liu
authors.forename: Dan
authors.initials: D
authors.lastname: Luo
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D051546:Cyclooxygenase 2 / Q000378:metabolism; D005260:Female; D005419:Flavonoids / Q000494:pharmacology*; D019394:Ki-67 Antigen / Q000032:analysis; D051379:Mice; D008810:Mice, Inbred C57BL; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis / Q000187:drug effects; D020011:Protective Agents / Q000494:pharmacology*; D012867:Skin / Q000033:anatomy & histology / Q000737:chemistry / Q000528:radiation effects*; D012878:Skin Neoplasms / Q000517:prevention & control*; D014466:Ultraviolet Rays / Q000009:adverse effects*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D005419:Flavonoids; D019394:Ki-67 Antigen; D018809:Proliferating Cell Nuclear Antigen; D020011:Protective Agents; C038044:baicalin; D051546:Cyclooxygenase 2